I would have added more detail about how to apply this to being a student, a mother, a waitress. David Allen claims it works well for all people, but it would be good to have more examples outside of the management world.

I would have explored in more details the character traits and habits that are required to stay consistent with the GTD approach. Some of this comes out at the very, very end of the book. Would be good to have this earlier.

I would have spent more time talking about regular tasks routines and other checklists. This is assumed at many points in the book, especially in the chapters on perspective. But maintaining routines other than the weekly review is not explicitly taught at any point in the GTD approach.

I would have included more sections that encourage people to buy stationary. Everyone likes buying stationary. That was the fun thing about the first book: the excuse to buy stationary. Some new permission to go shopping in that paradise called the office supply store would have been cool.